# Screening for Hepatitis B Virus Infection in Adolescents and Adults
## Purpose of the protocol
To provide updated recommendations for screening asymptomatic, nonpregnant adolescents and adults for Hepatitis B Virus (HBV) infection, aiming to prevent chronic liver disease and improve overall health outcomes.

## Target population
- Asymptomatic, nonpregnant adolescents and adults who:
    - Were vaccinated before being screened for HBV infection
    - Are at increased risk for HBV infection (including factors such as geographic origin and behavioral risks)
- Increased-risk criteria include:

    - Persons born in regions with HBsAg prevalence >= 2%
    - US-born persons whose parents are from regions with HBsAg prevalence >= 8% (and who were not vaccinated as infants)
    - HIV-positive persons
    - Persons with injection drug use (either past or current)
    - Men who have sex with men
    - Household contacts or sexual partners of persons with HBV infection

## Recommendation
- The USPSTF recommends screening for HBV infection in adolescents and adults at increased risk.
- Grade: B recommendation
- Method: Screen using the HBsAg test followed by a confirmatory test for initially reactive results.

## Importance
- Prevents chronic liver disease and liver-related complications including:
    - Cirrhosis and liver cancer
    - Liver failure
- Addresses public health issues:
    - As many as 68% of people with HBV are unaware of their infection
    - Delays in medical evaluation and treatment can lead to significant morbidity and mortality
- Improves early detection and linkage to care, thereby reducing transmission and improving health outcomes

## Conclusion
Screening for HBV in adolescents and adults at increased risk is associated with moderate net benefit. This recommendation is based on evidence that supports the accuracy of HBsAg testing and the effectiveness of antiviral treatments in improving health outcomes such as reducing mortality, risk of cirrhosis, and incidence of hepatocellular carcinoma.

For detailed guidance and updates, please consult the full recommendation statement on the USPSTF website.